The object of this exercise is to learn how to use and control a solar sail. Ikaros gave an excellent proof of concept, as it showed that it changed its velocity due to light pressure. The orbit that LightSail 2 is in gives the flight controllers plenty of opportunity to turn the sail “with the wind” and “into the wind.”* My expectation is that something will go wrong, they will lose the sail, and they will learn an important lesson about the hazards to sailing with photons. If nothing goes wrong, then they will have to wait for another sail before learning that lesson.

In the case of a polar orbit, one in which the sail is always in sunlight, then the acceleration would always be away from the sun, perpendicular to its orbital plane around the Earth, and not in a direction that changes the apogee or perigee. Counterintuitively, its orbit would not change as dramatically in such a polar orbit. Most likely the plane of the orbit would change by a few feet, or less, away from the Earth’s center of mass, where the direction of gravity would keep the plane from moving any farther (sine of the gravity vector balances the solar force on the sail).

* Everyone, please note that solar sails use the momentum of photons, not the particles of the solar wind.

pzatchok: I can’t answer your specific question. However, I do know the Japanese in 2010 did put a solar sail in a solar orbit, called Ikaros, and used sunlight to adjust its orbit. Unfortunately their website never provided much additional information. See the links here.

I fully understand their budgetary concerns.

pzatchok wrote: “If they had placed it into a polar orbit it would have lasted longer in orbit.”

And if unicorns had wings we’d all be saints. The Planetary Society purchased the satellite and the launch vehicle it could afford. In the past few decades it has been hard enough to get anything like this even into orbit. To nitpick them because they are doing this technology test in Earth orbit is quite unseemly. It does not do you credit.

Sail needs Solar Winds, and good Solar activity.
Sunspots ON ! Flares, STANDBY !

Fair winds and following Seas LightSail-2 !!

Pay particular attention to the rude admonishments, because in all likelihood:
“I’m sorry, but you have not found a meteorite.”

Amazingly: “most things that fall from the sky are not meteorites.“

It does not matter that the back side is shiny, as only the side toward the light source (the sun) will do the propulsive work. A solar sail is very different from a radiometer. An advantage to having two shiny sides is that it does not matter which side is toward the sun and doing the propulsion, which may give the controllers more options and freedom.

Making the “other” side not shiny would make the sail heavier, reducing its performance.